Cook the pasta according to the package directions. Rinse with cold water and set aside.,______,Prepare the dressing by combining the guacamole, juice of the remaining lime, buttermilk, cumin, salt and pepper in a medium sized bowl.,In a large bowl combine the cooled pasta, beans, veggies and the cilantro. Pour the dressing over the salad and mix to combine. Serve the same day it is prepared.